Haymarket Square riot

Haymarket Square riot, outbreak of violence in Chicago on May 4, 1886. Demands for an eight-hour working day became increasingly widespread among American laborers in the 1880s. A demonstration, largely staged by a small group of anarchists, caused a crowd of some 1,500 people to gather at Haymarket Square. When policemen attempted to disperse the meeting, a bomb exploded and the police opened fire on the crowd. Seven policemen and four other persons were killed, and more than 100 persons were wounded. Public indignation rose rapidly, and punishment was demanded. Eight anarchist leaders were tried, but no evidence was produced that they had made or thrown the bomb. They were, however, convicted of inciting violence, although no evidence was presented that they knew the bomber, who was never discovered. Four were hanged, one committed suicide, and the remaining three—after having served in prison for seven years—were pardoned (1893) by John P. Altgeld, governor of Illinois, on the ground that the trial had been patently unjust. The incident was frequently used by the adversaries of organized labor to discredit the waning Knights of Labor movement.

See studies by H. David (1936), P. Avrich (1984), and J. Green (2006).